The present invention relates to data accumulating devices and, more particularly, to cyclometer registers for data accumulating devices.
Cyclometer registers are commonly employed for accumulating measured quantities such as, for example, distance, time and other types of data. A common type of cyclometer register is found in an electric meter for totalling the number of rotations of a rotor disk to store and indicate the amount of electricity consumed by a load. Although the reset mechanism of the present invention may be usable in other measurement devices, an embodiment of the invention applied to registers for electric meters is selected as the environment in which the invention is described.
Cyclometer registers conventionally consist of a plurality of cyclometer drums on a common shaft each having the numerals 0-9 disposed on the peripheral surface thereof. The reading of the cyclometer register is made up of the series of numerals formed by the set made up of one numeral from each of the cyclometer drums. The lowest-significance one of the cyclometer drums is driven by a process whose data is to be measured. A set of carry pinions are interposed between adjacent ones of the cyclometer drums. As a cyclometer drum completes a revolution and performs a transition from 9 to 0, the interposed carry pinion advances or indexes the next higher cyclometer drum by one digit.
It is desirable to provide a mechanism for resetting all of the cyclometer drums to some known value such as, for example, zero. This is conventionally performed by ratchet devices which are spring-loaded to idle against the stationary drum shaft during normal operation. When the drum shaft is rotated, each ratchet device begins rotating its cyclometer drum as it reaches a certain relationship therewith to finally rotate all cyclometer drums together to the desired setting.
The desire to reduce the power burden for driving electric meters encourages the use of low-torque driving apparatus therein. Ratchet-type reset mechanisms of the prior art, by idling against the cyclometer drum shaft during normal operation, add an undesirable amount of friction to the operation of the register.